conf: add an error if the openssl_conf section isn't found.

Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/12602)

crypto/conf/conf_err.c

@@ -1,6 +1,6 @@
 /*
  * Generated by util/mkerr.pl DO NOT EDIT
- * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -36,6 +36,8 @@ static const ERR_STRING_DATA CONF_str_reasons[] = {
     {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_NO_SUCH_FILE), "no such file"},
     {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_NO_VALUE), "no value"},
     {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_NUMBER_TOO_LARGE), "number too large"},
+    {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION),
+    "openssl conf references missing section"},
     {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_RECURSIVE_DIRECTORY_INCLUDE),
     "recursive directory include"},
     {ERR_PACK(ERR_LIB_CONF, 0, CONF_R_SSL_COMMAND_SECTION_EMPTY),

crypto/conf/conf_mod.c

@@ -107,8 +107,13 @@ int CONF_modules_load(const CONF *cnf, const char *appname,
     OSSL_TRACE1(CONF, "Configuration in section %s\n", vsection);
     values = NCONF_get_section(cnf, vsection);
 
-    if (!values)
+    if (values == NULL) {
+        if (!(flags & CONF_MFLAGS_SILENT)) {
+            CONFerr(0, CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION);
+            ERR_add_error_data(2, "openssl_conf=", vsection);
+        }
         return 0;
+    }
 
     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
         vl = sk_CONF_VALUE_value(values, i);

crypto/err/openssl.txt

@@ -2276,6 +2276,8 @@ CONF_R_NO_SECTION:107:no section
 CONF_R_NO_SUCH_FILE:114:no such file
 CONF_R_NO_VALUE:108:no value
 CONF_R_NUMBER_TOO_LARGE:121:number too large
+CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION:124:\
+	openssl conf references missing section
 CONF_R_RECURSIVE_DIRECTORY_INCLUDE:111:recursive directory include
 CONF_R_SSL_COMMAND_SECTION_EMPTY:117:ssl command section empty
 CONF_R_SSL_COMMAND_SECTION_NOT_FOUND:118:ssl command section not found

include/openssl/conferr.h

@@ -68,6 +68,7 @@ int ERR_load_CONF_strings(void);
 # define CONF_R_NO_SUCH_FILE                              114
 # define CONF_R_NO_VALUE                                  108
 # define CONF_R_NUMBER_TOO_LARGE                          121
+# define CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION   124
 # define CONF_R_RECURSIVE_DIRECTORY_INCLUDE               111
 # define CONF_R_SSL_COMMAND_SECTION_EMPTY                 117
 # define CONF_R_SSL_COMMAND_SECTION_NOT_FOUND             118